Quantifying the Effects of Uncertainty in Correlating Fatigue Life Simulation with Physical Tests

Описание: Presented by Andrew Halfpenny of HBK

Fatigue is defined as: “the progressive weakening of a material caused by cyclic or otherwise varying loads, even though the resulting stresses are well within the static strength limits.” Fatigue failures often initiate at a microscopic level and no two components are identical at this scale. Materials are inherently variable, and for most engineering purposes they are modelled empirically to account for these inconsistencies. Furthermore, uncertainties in loading, residual stresses, and other effects, compound to have a significant influence on the overall uncertainty of fatigue life.
This presentation demonstrates how fatigue life simulations may be correlated with physical reliability tests whilst accounting for the wide-ranging uncertainty in life measurements. A case study demonstrates how the methods are applied to an air-cooled intercooler. A comparison is made between fatigue simulation and physical reliability test results. The simulation is shown to offer excellent correlation with the experimental measurements. No further improvements in the model were deemed necessary and the model is considered a suitable platform for performing design simulations and for extrapolating the reliability statistics.